Gate valve



ul 19 192 J 7 A. M. MCJRRlsoN GATE VALVE Filed Dem 1o. 192;

- mechanism has been taken up.

4|50 nism fully extend Il c osure partly. open.

' Patentes July `19.y 1927.

iU-N'ITED 'STATES PATENT OFFICE.

ANDREW I. IOBIFISON, I' DUBUQUE, IOWA.

'een vaLvn.

Application nl e'dbeceinber 10, 1993. Serial lo. 810,588.

f This invention relates broadly to iluid valves wherein it is desirable to provide a delayed action of the actualropeni'ng o f said valve whilefthe operating mechanism is 5 given its vinitial movement.

It is an object of this invention to provide a locking valve wherein a resilient lost.

motion is provided in the -valve operating mechanism adapted to retain the valve in a fully sealed condition even though the'operating mechanism is not positioned to posiftively hold the valve sealed. It is alsol an object ofthis invention to provide a double gate valve wherein the vsep- 1,5 arate gates are loosely hung from the operi ating mechanism and slightly s read thereby when the mechanism is move to close the valve.

Itis a further object of this invention to 20 permit partial retraction of the operatin mechanism afterthe valve has been close without the possibility of the valve closure becomin unseated and allowing "a seepage of liqui therethrough. It 1s another object of this invention to provide a double gate valve wherein the sepf are forced against their seats by contacting central bosses on .the

' gat, whereby the gates are given a uniform' lrpoints of contact with their seats.` j

Itis still separate gates are free to individually align. 85 `themselves with their seats.'

Other and further important objects of this invention will be apparent from the disthe specification 'and the accom- Plnymg nWmgS-lf. '-r 0f' in a preferred form) is F1 s on mg to Figures 1 and 2 with the valve another object of this invention 1 to provide a double gate valvewhereinthe lockin vby .a aidera le playin such ay chain even i-f it is vdrawn up as ti over aspoke o the vwheel 22 may be ina As shown on the drawings:

A valve bod 10 is shown of theso gate type w erein inlet and outlet pipe threads are represented at 11 and oppositely disposed valve seats are shown at 12. These valve seats are parallel' but may be inclined if so vdesired/fte'. give a wedging action to valve discs 13 which as shown aremade as separate and duplicate closures for each seat. These valve discs areprovided with a central boss 14 formed to engage either a wedge or cone pointedmember 15 having a collar 16 which eng in slots 17 in the valve discs, the ,slots ing about twice the width of the collar so that whenstarting to retract the discs into a pocket 18 provided therefor in thevvalve.body,the wedge member 15 is disengaged from the bosses'14 before'the collar 16V eng es the upper surface. of the slots 17 to lift t e valve discs. This allows the valve discs to separate from their seats and permits smooth and nearly frictionless withdrawal thereof into the pocket.; By constructing these discs as separate units for each valve seat they are rendered self aligning and if desired the valve seats need not be parallel but may be made with a dive'xgilng angle. i e valve operating mechanism comprises a valve bonnet 19 screwed onto the valve body and containing-threads (not shown) to' engage threads 20 on a valve stem 21 :for advancing said stem. The stem is provided with the usual operating wheel 22. A' hinged bar 23 is pivoted to the bonnet atj 24 an guided at 25. This bar 23 has suit- ,4 able apertures to receive a chain 26 assed locked through-the operating wheel 22 and adlock 27; There is necessarily contly as possible, andv moreposition to interfere with the chain when the valve is entirel closed. Under such 'circumstances they ve stem and wheel must be l00, bcked olf slightly to permit locking the c m. Y

The threaded portion ofthe valve stem 21 terminates in a shoulder 28-below which is a cylindrical section 29 serving as a' spring 105 guide. Below the guide anarrow shank 30 carries a head 31'which fits into a T slot- 32 in the. top of the wedge (15) withdsuicient up and downlost motion to-provide fproximately a or more of e Il called valve stem between the extreme movements of the head 31 in the T slot. A coiled spring 33 surrounds the spring guide and one end thereof bears against the shoulder 28, while the other end bears against the wedge to' hold the latter at its extreme position relative to the head 31. -It is to be understood that if a solid wedge-shaped gate is used with diverging valve seats, the shank 30 and head 31 engage in a similar T slot inthe gate itself as the wedge member (15) is therefore unnecessary.

The operation of this valve is as follows. Assume that the valve is in the position of Figure 3v and is being closed. Rotation of the valve stem lowers the valve discs until they come to rest without pressurev against the valve seat. Further rotation of the valve stem brings the cone point of 'the wedge member 15 against the central bosses 14 on the valve discs, the spring 33 serving to hold thev wedge extended as shown in Figure 2. Still further rotation of the valve stem compresses ,the spring 33 until the head 31 comes into contact with the bottom of the T slot 32 as in Figure 1 whereupon any desired pressure may be vpositively applied to the valve discs to assure a positive closure. Such pressure on the central bosses 14 is of course uniformly distributed over the .valve seat faces. The spring 33 is purposely made suficiently stiff to maintain the wedge and Y valve discs in position against any fluid pressure the valve is designed for, so that after forcing the valves to a seat the valve stem may be retracted to an extent limited only to the play or lost motion between the head 31 and T slot 32. Thus for example if the valve stem wheel is locked with a chain when the head 31 presses on'the member 15, all the slack ordinarily found in such a chain und padlock can be taken up by a reverse rotation of the wheel without loosening the valve discs and thereby permit-ting seepage of liquids through the valve.

I am aware that many changes may be made, and numerous details of construction may be varied through a widev range without departing from the principles of this ine vention, and I therefore do not purpose lim- `valve discs, said wedge and the inner faces of said valve. disks having directly engaging means supporting the disks on the wedge and providing for limited relative movement of the wedge with respect to the disks.

2. A valve including a pair of valve disks, a valve stem, a valve actuating member in a single piece between the disks, having means at its lower end engaging the disks centrally of their adjacent faces to shift the same laterally, a lost motion connection between. the upper vend of said actuating member and the stem, means to normally maintain said actuating member in extended position on the stem, and an outstanding part on the actuating member to engage the adjacent faces of the disks for raising the latter, said disks having recesses in their said inner faces in which the outstanding part of the actuating member movably seats.

3. A valve including a pair of valve disks having bosses centrally of their inner races, a valve stem, a. c lindrical valve actuating member in a sing e piece between the disks having a conical lower end. engaging and cooperating with said bosses of the disks,

said actuating member having a socket in its upper end in which the lower end of the valve stem isv rotatable and has a limited lon- 'gitudinal movement, a, spring associated with the valve stem and engaging said actuating member to normally hold the same in extended position on the valve stem, an outstanding rib onthe actuating member intermediate its ends, said valve disks 'having recesses in lportions of their inner faces into which re cesses the rib of the actuating member extends and/is movable.

In testimony whereof I have hereunto subscribed my name.'

ANDREW M. MoRRisoN.

noV 

